Cathode placement in a gas discharge closing switch

Abstract

In a closing switch having a control electrode and a cathode within a gas-filled cavity, the cathode has a distal portion spaced from the control electrode by a distance corresponding to the minimum breakdown voltage of the closing switch. Thus, the cathode is placed such that gas breakdown adjacent the distal portion occurs at a control voltage lower than the voltage required to initiate such breakdown adjacent the portion of the cathode closest to the control electrode.

What is claimed is: 
     
       1. A gas discharge closing switch comprising: a housing containing a gas at a preselected pressure;   a control electrode within the housing for applying a control voltage to initiate breakdown of said gas;   a cathode structure located within the housing and having a proximal portion relative to the control electrode;   the cathode structure disposed relative to the control electrode to initiate said breakdown at a distal portion of the cathode structure more remote from the control electrode than said proximal portion; and   the distal portion of the cathode structure spaced from the control electrode by a distance corresponding to the minimum breakdown voltage within the closing switch at said preselected gas pressure.   
     
     
       2. A gas discharge closing switch comprising: a housing containing a gas at a preselected pressure;   a control electrode within the housing for applying a control voltage to initiate breakdown of said gas;   a cathode structure located within the housing and having a proximal portion and a distal portion relative to the control electrode;   the distal portion of the cathode structure spaced from the control electrode by a distance corresponding to the minimum breakdown voltage within the closing switch at said preselected gas pressure.   
     
     
       3. The gas discharge closing switch of claim 2 wherein: the minimum breakdown voltage within the housing corresponds to the minimum of a Paschen curve.   
     
     
       4. A gas discharge closing switch comprising: housing means containing gas at a preselected pressure;   control electrode means within the housing for applying a control voltage;   cathode means located within the housing and having a proximal portion and a distal portion relative to the control electrode means;   the cathode means spaced from the control electrode means such that breakdown of said gas occurs adjacent said distal portion at a control voltage lower than the control voltage required to initiate such breakdown adjacent the proximal portion of the cathode means.   
     
     
       5. A gas discharge closing switch comprising: a housing containing a gas at a preselected pressure;   a control electrode within the housing for applying a control voltage;   a cathode structure located within the housing and having a proximal portion and a distal portion relative to the control electrode;   the cathode structure spaced from the control electrode such that breakdown of said gas occurs adjacent the distal portion of the cathode structure before such breakdown is initiated at the proximal portion of the cathode structure as the control voltage is increased.   
     
     
       6. The gas discharge closing switch of claim 5 wherein: the distal portion of the cathode structure is spaced from the control electrode by a distance corresponding to the minimum breakdown voltage of the closing switch at said preselected gas pressure.   
     
     
       7. A method of manufacturing a gas discharge closing switch comprising the steps of: providing a housing for containing a gas at a preselected pressure;   providing a control electrode within the housing;   providing a cathode structure within the housing, the cathode structure having a proximal portion and a distal portion relative to the control electrode;   locating the cathode structure within the housing such that breakdown of the gas adjacent the distal portion of the cathode structure occurs at a control voltage lower than the control voltage required to initiate such breakdown adjacent the proximal portion of the cathode structure.   
     
     
       8. The manufacturing method of claim 6 wherein the step of locating the cathode structure within the housing further comprises: positioning the cathode structure so that the distal portion is spaced from the control electrode by a distance corresponding to the minimum breakdown voltage of the closing switch at said preselected gas pressure.   
     
     
       9. The manufacturing method of claim 6 wherein: the cathode structure is positioned in the housing with said distal portion located at an end of the cathode structure opposite to the control electrode.   
     
     
       10. A gas discharge closing switch comprising: a housing containing a gas at a preselected pressure;   a control electrode within the housing for applying a control voltage to initiate breakdown of said gas; and   a cathode structure located within the housing and beneath the control electrode, the cathode structure having an upper half and a lower half;   the cathode structure spaced from the control electrode such that said breakdown occurs adjacent the lower half of the cathode structure at a control voltage lower than the control voltage required to initiate such breakdown adjacent the upper half of the cathode structure.   
     
     
       11. A gas discharge closing switch comprising: a housing containing a gas at a preselected pressure;   a control electrode within the housing for applying a control voltage to initiate breakdown of said gas; and   a cathode structure located within the housing and beneath the control electrode, the cathode structure having a proximal portion and a distal portion relative to the control electrode, the distal portion being adjacent a lower end of the cathode structure;   the cathode structure spaced from the control electrode such that said breakdown occurs adjacent the distal portion of the cathode structure at a control voltage lower than the control voltage required to initiate such breakdown adjacent the proximal portion of the cathode structure.   
     
     
       12. A gas discharge closing switch comprising: a housing containing a gas at a preselected pressure;   a control electrode within the housing for applying a control voltage to initiate breakdown of said gas;   a cathode structure having a thermionic coating and located within the housing, the cathode structure having a proximal portion and a distal portion relative to the control electrode, the distal portion being adjacent a lower end of the cathode structure;   the cathode structure spaced from the control electrode such that said breakdown occurs adjacent the distal portion of the cathode structure at a control voltage lower than the control voltage required to initiate such breakdown adjacent the proximal portion of the cathode structure.